tril·​lion | \ˈtri(l)-yən \

Definition of trillion 

1 : a number equal to 1,000 times one billion — see Table of Numbers

2 : an indeterminately large number a trillion mosquitoes out tonight

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Other Words from trillion

trillion adjective
trillionth \ ˈtri(l)-​yən(t)th \ adjective or noun

Examples of trillion in a Sentence

Recent Examples on the Web

Ytterbium ticks trillions of times a second, and each of those ticks has to be incredibly precise. Avery Thompson, Popular Mechanics, "Here Is the World's Most Stable Atomic Clock," 28 Nov. 2016 Their planet might be orbited by billions or trillions of geosynchronous satellites instead of our measly 400. NBC News, "Alien satellites might offer a new way to find E.T.," 19 Mar. 2018 These particles can reach Earth with energies of hundreds of trillions of electron volts — dwarfing the mere 6.5 trillion electron volts of the protons circulating through the Large Hadron Collider in Europe. Amina Khan,, "After years of searching, scientists finally trace high-energy neutrinos to a distant blazar," 12 July 2018 Win McNamee/Getty Images Tax cuts have clipped trillions of dollars off federal government revenues in recent years, largely to the benefit of the richest Americans. Emily Stewart, Vox, "America’s getting $10 trillion in tax cuts, and 20% of them are going the richest 1%," 11 July 2018 In the post-crisis period, it was discovered that the rate -- which helps price trillions of dollars worth of other assets -- was being gamed or manipulated by traders., "The World’s Most Controversial Interest Rate Returns," 23 Mar. 2018 Who has been electing politicians who, year after year, keep piling up the national debt, now in the untold trillions of dollars? Republicans and Democrats have done it and millennials — conservative or liberal — have had nothing to do with it. John Kass,, "30-year-old slacker evicted from parents' basement could prove doubters wrong, lead the millennials," 26 May 2018 But protecting the human species from the end of life on Earth could save trillions of lives. Derek Thompson, The Atlantic, "Is Colonizing Mars the Most Important Project in Human History?," 29 June 2018 The economic stress of disasters is now regularly measured in billions—and even sometimes in trillions of dollars—and has measureable impacts to GDP. Jeff Schlegelmilch, Fortune, "The 2018 Hurricane Season Is Here. We Can’t Just Rely on the Federal Government to Help Us Prepare," 30 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'trillion.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of trillion

1690, in the meaning defined at sense 1

History and Etymology for trillion

French, from tri- + -illion (as in million)

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Statistics for trillion

Last Updated

10 Nov 2018

Look-up Popularity

Time Traveler for trillion

The first known use of trillion was in 1690

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More Definitions for trillion



English Language Learners Definition of trillion

: the number 1,000,000,000,000 : one thousand billion

: a very large amount or number

: the number 1,000,000,000,000,000,000 : one million million million


tril·​lion | \ˈtril-yən \

Kids Definition of trillion

: a thousand billions

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